21394544 has 10 divisors (see below), whose sum is σ = 41451960. Its totient is φ = 10697264.

The previous prime is 21394519. The next prime is 21394561. The reversal of 21394544 is 44549312.

It is a self number, because there is not a number n which added to its sum of digits gives 21394544.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 668564 + ... + 668595.

It is an arithmetic number, because the mean of its divisors is an integer number (4145196).

Almost surely, 2^21394544 is an apocalyptic number.

It is an amenable number.

21394544 is a deficient number, since it is larger than the sum of its proper divisors (20057416).

21394544 is a wasteful number, since it uses less digits than its factorization.

21394544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1337167 (or 1337161 counting only the distinct ones).

The product of its digits is 17280, while the sum is 32.

The square root of 21394544 is about 4625.4236562719. The cubic root of 21394544 is about 277.6095133593.

The spelling of 21394544 in words is "twenty-one million, three hundred ninety-four thousand, five hundred forty-four".